Portable automatic coating brush



Oct. 18, 1966 .EIZO NAKAYA ETAL 3,278,975

PORTABLE AUTOMATIC COATING BRUSH 2 Sheets-Sheet 2 Filed Aug. 20, 1964 ElZO NAKAYA ETAL 3,278,975

PORTABLE AUTOMATIC COATING BRUSH Oct. 18, 1966 Filed Aug. 20, 1964 2 Sheets-Sheet 1 United States Patent 3 278,975 PORTABLE AUTOMATIC COATING BRUSH Eizo Nakaya, deceased, late of Setagaya-ku, Tokyo-to, Japan, by Sakae Nakaya and Chiyo Nakaya, Kita-ku, Tokyo-to, Eiko Ishikawa, Hatogaya-machi, Kazuko Yabe, Horinouchi-machi, Yoko Uryu, Kawaguchi-shi, Taiko Saito, Urawa-shi, and Chieko Nakaya, Kita-ku, Tokyo-to, Japan, heir and heiresses, assignors to Yugen Kaisha Shin Nakaya Tosoki, Tokyo-to, Japan, a limited company of Japan Filed Aug. 20, 1964, Ser. No. 390,791 Claims priority, application Japan, Aug. 24, 1963, 38/ 44,021 2 Claims. (Cl. 15-550) This invention relates to portable automatic coating brushes and more particularly to a novel coating brush wherein coating material such as paint is automatically. fed to the brush.

In general, coating materials such as paint and varnish are applied manually by dipping a brush in a paint can and then moving the brush back and forth along the surface to be coated. However, in high places such coating operations are very dangerous and frequent movement of the brush between the work to be painted and the paint can requires hard labor and much time, whereby the coating efiiciency is limited. Also, waste of the coating material is substantial.

It is therefore an object of this invention to provide a portable coating brush wherein a regulated quantity of a coating material is constantly fed to the brush.

Another object of this invention is to provide a novel automatic coating brush capable of forming uniform coatings with high efiiciency without any significant loss of the coating material.

Still another object of this invention is to provide a portable automatic coating brush which can utilize rapiddrying coating material.

Yet another object of this invention is to provide a novel portable automatic coating brush wherein the main portion of the coating material is constantly circulated through a closed circuit without being exposed to the atmosphere and a portion of the coating material is selectively supplied to the brush.

In accordance with one embodiment of this invention, these and other objects are attained by providing an automatic coating brush comprising a handle, a brush assembly detachably mounted on one end thereof, inlet and outlet passages extending through the handle to circulate the coating material through a closed circuit, an adjustable valve connected between the inlet and outlet passages to regulate the quantity of the circulating coating material, a passage extending through the handle between the brush assembly and the adjustable valve to supply a portion of the circulating coating material to the brush assembly and a stop valve connected in the last mentioned passage.

The invention will be better understood from the following detailed description of preferred embodiments thereof taken in connection with the accompanying drawings in which like parts are designated by like reference characters, and in which:

FIG. 1 is a longitudinal cross sectional view of one embodiment of this invention;

FIG. 2 is a side elevation of the automatic coating brush shown in FIG. 1;

FIG. 3 is a top plan View of the automatic coating brush shown in FIGS. 1 and 2; and

FIG. 4 is a longitudinal cross section of a modified embodiment of this invention.

Referring now to the accompanying drawing, more particularly to FIGS. 1 to 3, there is shown an automatic portable coating brush comprising a main body A in the form of a handle 1 bored with a paint or coating material discharge passage 3 which is opened at the front end surface 2, a paint inlet passage 5, and a paint outlet passage 6 which are open at the rear end 4 of the handle. These passages communicate together in the handle via a valve chest 7, a bore 8, and a valve chest 9. A stop valve 10 movable perpendicularly to the longitudinal axis of the handle A is provided in the valve chest 7 to close and open said discharge passage 3, and an adjustable valve 11 is provided in the valve chest 9 to move in a similar direction to adjust the opening for said paint inlet passage 5. On the free end of a valve stem 12 of the stop valve 10, there is suitably secured a push button 13 which is biassed outwardly by means of a spring 14 to normally project beyond the surface of the main body A thus shutting off the passage 3.

At one end of a valve stem 15 of the adjustable valve 11, there is provided a threaded head 16 adapted to be received in a double nut 17 which in turn is screwed into an opening of the valve chest 9. Thus, by turning the threaded head 16 a gap between the other end of the valve stem 15 and a valve seat 18 is adjusted to set the inlet quantity of the coating material to any desired value.

Suitable packings 19 and 19a are provided around valve stems 12 and 15, respectively, and a ring shaped stopper 21 is provided to prevent the valve stem 15 from falling off. Also, a slidable operating member 22 is provided' to press down the push button 13 to open or close the communication between the passage 3 and the valve chest 7.

A brush assembly B comprising a plurality of bundles of bristles 24 secured to a brush frame 23 and a base plate 25 is removably connected to the front end surface of the handle A by means of machine screws 27. A plurality of short pipes 26 are connected to the base plate 25 to feed the coating material to the brush. Instead of using short pipes 26, a number of perforations of circular, sector or annular shape may be provided. A reinforcing member 28 is provided to surround the bundles of bristles 24 to prevent them from falling. As shown by the dot-dash lines, hoses 29 and 30 leading to a paint pump and paint tank, which are not shown, but connected in a closed circuit, are connected to nipples communicating with the inlet and outlet passages, respectively.

The modification shown in FIG. 4 is substantially identical with the first embodiment except that the front end surface 2 is inclined at an angle with respect to the main body A, corresponding parts being designated by the same reference numerals.

The operation of the portable automatic coating brush of the above described construction according to the invention is as described hereinbelow.

A suitable coating material such as paint is supplied to the inlet passage 5 through the hose 29 under a suitable pressure of about 0.5 kg./ ch1 gauge, for example. For more viscous coating material, such as an adhesive, 21 higher pressure of about 7 kg./cm. is preferable. With the stop valve 10 closed, the coating material circulates through the closed circuit including the passage 5, the adjustable valve 11, its valve chest 9, the outlet passage 6, and the pump and paint tank, not shown.

When the stop valve 10 is opened, a portion of the coating material is supplied to the brush assembly B through the bore 8, the valve chest 7, and the discharge passage 3, thereby to impregnate the bristle bundles 24 through short pipes 26.

As can be easily understood, the quantity of the coating material fed can be adjusted to any desired value by turning the threaded head 16 to adjust the degree of opening of the adjustable valve 11. Under normal coating condi- 3 tions, 50 cc. per minute of impregnation is preferable for a rate of feeding of 2 liters per minute from the paint pump.

Thus, this invention provides a novel portable automatic coating brush which not only is easy to manipulate but can provide uniform and esthetically pleasing coated films. Moreover, as the coating material is constantly circulated through a closed circuit Without being exposed to air, deterioration and loss of the coating material can be minimized. Thus, the novel coating brush makes possible the application of a fast drying type coating material.

Workmen can use the novel portable automatic brush on the ground or at elevated places to apply the coating material to any surface of the work such as walls, ceilings, and the like without the necessity of frequent dipping of the brush in the paint can. Further, the quantity of the coating material applied and, hence, the thickness of the film formed can be easily and simply adjusted by varying the opening of the adjustable valve 11, and the feeding of the coating material to the brush assembly can be stopped without stopping the paint pump. Thus the novel coating brushes can be advantageously used for applying coating materials to ships, iron frames, bridges, iron towers, buildings, inside and outside of water pipes in hydroelectric power stations, freight cars, chemical plant and factory buildings.

While the invention has been shown and described in connection with a few preferred embodiments thereof, it should be understood that this invention is not limited thereto but includes any modifications and alterations as fall within the true spirit and scope of this invention.

4 What is claimed is: 1. A portable automatic coating brush comprising a handle, a brush assembly mounted on one end of said handle, means defining a paint inlet passage and a paint outlet passage extending axially through said handle, an adjustable valve within said handle for interconnecting the inner ends of said paint inlet and outlet passagesin proximity to said one end for regulating the quantity of paint circulating through said inlet and outlet passages, said adjustable valve including a valve chest located .between the inner ends of said inlet and outlet passages, means defining a passage operably related between'the valve chest and the brush assembly for supplying a portion of the circulating paint to the brush assembly,'and a stop valve operably related to said passage between the valve chest and the brush assembly.

2. The portable automatic painting brush as claimed in claim 1 in which said paint inlet and outlet passages are adapted to be connected to a paint pump and paint tank for constituting a closed circuit for circulating the paint.

References Cited by the Examiner UNITED STATES PATENTS D. 167,775 8/1952 Schmidt 15-143 .X 1,048,778 12/1912 Wood 15-143 .X 2,283,314 5/1942 Ckola 15-24 2,959,801 11/1960 Pelham 15603 CHARLES A. WILLMUTH, Primary Examiner.

S. E. BECK, Assistant Examiner. 

1. A PORTABLE AUTOMATIC COATING BRUSH COMPRISING A HANDLE, A BRUSH ASSEMBLY MOUNTED ON ONE END OF SAID HANDLE, MEANS DEFINING A PAINT INLET PASSAGE AND A PAINT OUTLET PASSAGE EXTENDING AXIALLY THROUGH SAID HANDLE, AN ADJUSTABLE VALVE WITHIN SAID HANDLE FOR INTERCONNECTING THE INNER ENDS OF SAID PAINT INLET AND OUTLET PASSAGES IN PROXIMITY TO SAID ONE END FOR REGULATING THE QUANTITY OF PAINT CIRCULATING THROUGH SAID INLET AND OUTLET PASSAGES, SAID ADJUSTABLE VALVE INCLUDING A VALVE CHEST LOCATED BETWEEN THE INNER ENDS OF SAID INLET AND OUTLET PASSAGES, 